Passively adjustable elements for earth-boring tools and related tools and methods

ABSTRACT

Passively adjustable elements for earth-boring tools may include a housing and an element located at least partially within the housing. A piston may be secured to the element, the piston configured to drive extension and retraction of the element relative to the housing. A first flow path may extend through the piston, through a first flow controller supported by the piston to permit fluid to flow at a first rate during retraction of the element. A second flow path may extend at least partially through the piston, through a second flow controller supported by the piston, to permit fluid to flow at a second, faster rate during extension of the element. A biasing element may bias the piston toward an extended position. An outer diameter of the piston may be less than or at least substantially equal to an outer diameter of the element.

FIELD

This disclosure relates generally to mechanisms for passively adjusting exposures of elements secured to earth-boring tools. More specifically, disclosed embodiments relate to mechanisms for passively adjusting exposures of elements secured to earth-boring tools that may enable the elements to retract slowly and extend more quickly while reducing size, staying within preferred pressure ranges, and simplifying installation procedures.

BACKGROUND

When forming or expanding a borehole in an earth formation, it may occasionally be desirable for certain features of an earth-boring tool to modify their exposure relative to one or more other components of the earth-boring tool. For example, the exposures of cutting elements, inserts, depth-of-cut-control elements, ovoids, wear pads, and/or stabilizer pads may be beneficially modified to change the aggressiveness with which the earth-boring tool removes the earth formation. For example, devices that enable passive modification of the exposure of elements on an earth-boring tool are disclosed in, for example, U.S. Pat. No. 9,255,450, issued Feb. 9, 2016, to Jain et al.; U.S. Patent App. Pub. No. 2017/0175454, published Jun. 22, 2017; U.S. Patent App. Pub. No. 2017/0175455, published Jun. 22, 2017, to Jain et al.; and U.S. patent application Ser. No. 15/662,821, filed Jul. 28, 2017, to Evans et al., the disclosures of each of which is hereby incorporated in its entirety herein by this reference.

BRIEF SUMMARY

Passively adjustable elements for earth-boring tools may include a housing and an element located at least partially within the housing and extendable and retractable relative to the housing. A piston may be located within the housing and secured to the element, the piston configured to drive extension and retraction of the element. The piston and the housing may cooperatively form a first chamber located at a first axial position along the piston and a second chamber located at a second, different axial position along the piston. A first flow path may extend from the first chamber, through the piston, through a first flow controller supported by the piston, to the second chamber, the first flow controller configured to permit fluid to flow from the first chamber to the second chamber at a first rate during retraction of the element and piston relative to the housing. A second flow path may extend from the second chamber, at least partially through the piston, through a second flow controller supported by the piston, to the first chamber, the second flow controller configured to permit fluid to flow from the second chamber to the first chamber at a second, faster rate during extension of the element and piston relative to the housing. At least one sealing element may be located between the piston and the housing to axially separate the first chamber from the second chamber. A biasing element may be positioned and configured to bias the piston and element toward an extended position. An outer diameter of the piston as measured in a direction at least substantially perpendicular to a direction of extension and retraction of the element may be less than or at least substantially equal to an outer diameter of the element.

Earth-boring tools may include a body and a passively adjustable element secured to the body. The passively adjustable element may include a housing and an element located at least partially within the housing and extendable and retractable relative to the housing. A piston may be located within the housing and secured to the element, the piston configured to drive extension and retraction of the element. The piston and the housing may cooperatively form a first chamber located at a first axial position along the piston and a second chamber located at a second, different axial position along the piston. A first flow path may extend from the first chamber, through the piston, through a first flow controller supported by the piston, to the second chamber, the first flow controller configured to permit fluid to flow from the first chamber to the second chamber at a first rate during retraction of the element and piston relative to the housing. A second flow path may extend from the second chamber, at least partially through the piston, through a second flow controller supported by the piston, to the first chamber, the second flow controller configured to permit fluid to flow from the second chamber to the first chamber at a second, faster rate during extension of the element and piston relative to the housing. At least one sealing element may be located between the piston and the housing to axially separate the first chamber from the second chamber. A biasing element may be positioned and configured to bias the piston and element toward an extended position. An outer diameter of the piston as measured in a direction at least substantially perpendicular to a direction of extension and retraction of the element may be less than or at least substantially equal to an outer diameter of the element.

Methods of using earth-boring tools having passively adjustable elements may involve engaging an earth formation utilizing an earth-boring tool. An element may be retracted at a first rate to a greater extent within a housing secured to a body of the earth-boring tool in response to engaging the earth formation utilizing the earth-boring tool by compressing a biasing element biasing the piston and the element toward an extended position while flowing a hydraulic fluid along a first flow path extending from a first chamber located at a first axial position along a piston secured to, and movable with, the element, through the piston, through a first flow controller supported by the piston, to a second chamber located at a second, different axial position along the piston. An outer diameter of the piston as measured in a direction at least substantially perpendicular to a direction of extension and retraction of the element may be less than or at least substantially equal to an outer diameter of the element. The element may be extended at a second, faster rate relative to the housing in response to reducing engagement with the earth formation utilizing the earth-boring tool by permitting the biasing element to move the piston and the element toward the extended position while flowing the hydraulic fluid along a second flow path extending from the second chamber, at least partially through the piston, through a second flow controller supported by the piston, to the first chamber; and fluidly isolating the first chamber from the second chamber utilizing at least one sealing element located between the piston and the housing.

BRIEF DESCRIPTION OF THE DRAWINGS

While this disclosure concludes with claims particularly pointing out and distinctly claiming specific embodiments, various features and advantages of embodiments within the scope of this disclosure may be more readily ascertained from the following description when read in conjunction with the accompanying drawings, in which:

FIG. 1 is a partial cutaway perspective view of an earth-boring tool including a passively adjustable element;

FIG. 2 is a cross-sectional side view of the passively adjustable element of FIG. 1 in a retracted state;

FIG. 3 is a cross-sectional side view of the passively adjustable element of FIG. 2 in an extended state;

FIG. 4 is a cross-sectional side view of another embodiment of a passively adjustable element;

FIG. 5 is a cross-sectional side view of another embodiment of a passively adjustable element;

FIG. 6 is a cross-sectional side view of another embodiment of a passively adjustable element; and

FIG. 7 is a cross-sectional side view of another embodiment of a passively adjustable element.

DETAILED DESCRIPTION

The illustrations presented in this disclosure are not meant to be actual views of any particular passively adjustable element, earth-boring tool, or component thereof, but are merely idealized representations employed to describe illustrative embodiments. Thus, the drawings are not necessarily to scale.

Disclosed embodiments relate generally to mechanisms for passively adjusting exposures of elements secured to earth-boring tools that may enable the elements to retract slowly and extend more quickly while reducing size, staying within preferred pressure ranges, and simplifying installation procedures. More specifically, disclosed are embodiments of mechanisms for passively adjusting exposures of elements secured to earth-boring tools that may include pressure-compensation mechanisms to compensate for temporary pressure differences between fluid chambers within the mechanisms for passively adjusting the exposures of the elements and unconventional arrangements for the chambers themselves and fluid passageways enabling fluid flow to and from the chambers.

As used herein, the terms “substantially” and “about” in reference to a given parameter, property, or condition means and includes to a degree that one of ordinary skill in the art would understand that the given parameter, property, or condition is met with a degree of variance, such as within acceptable manufacturing tolerances. For example, a parameter that is substantially or about a specified value may be at least about 90% the specified value, at least about 95% the specified value, at least about 99% the specified value, or even at least about 99.9% the specified value.

The term “earth-boring tool,” as used herein, means and includes any type of bit or tool used for aggressive (i.e., earth-removing), nonaggressive (i.e., sliding, non-earth-removing), or a combination of aggressive and nonaggressive contact with earth material during the formation or enlargement of a wellbore in a subterranean formation. For example, earth-boring tools include fixed cutter bits, core bits, eccentric bits, bicenter bits, reamers, stabilizers, mills, hybrid bits including both fixed and rotatable cutting structures, and other drilling bits and tools known in the art.

FIG. 1 is a partial cutaway perspective view of an earth-boring tool 100 including a passively adjustable element 102. The earth-boring tool 100 includes a body 104 to which the passively adjustable element 102 is secured. The passively adjustable element 102 may be positioned to contact earth material as the earth-boring tool 100 is advanced and to retract and extend in response to reaction forces from the earth material without providing active power to retract and extend that passively adjustable element (e.g., utilizing a motor or altering a flow path of drilling fluid through the earth-boring tool). For example, the passively adjustable element 102 may be configured as a depth-of-cut-control element or ovoid, as shown in FIG. 1, which may at least partially aggressively engage the earth material (i.e., may penetrate and remove at least some earth material) and at least partially passively engage the earth material (i.e., may slide against without removing the earth material) to modify the depth of penetration of cutting elements 106 also secured to the body 104. In other embodiments, the passively adjustable element 102 may be configured as, for example, a cutting element, a cutting insert (each of which may be configured to actively engage the earth material, at least when the passively adjustable element is in an extended state and optionally when the passively adjustable element is in a retracted state), a gage pad, and a stabilizer pad (each of which may be configured to passively engage the earth material).

Passively adjustable elements in accordance with this disclosure may be employed with a variety of earth-boring tools. For example, the earth-boring tool 100 depicted in FIG. 1 is configured as an earth-boring drill bit, specifically a fixed-cutter, earth-boring drill bit. The body 104 of the earth boring tool 100 may include blades 108 extending radially and axially outward from a remainder of the body 104, the blades 106 forming junk slots 110 rotationally between the blades 106. The cutting elements 106 may be secured to the blades 108 positioned proximate rotationally leading surfaces 112 of the blades 108. The earth-boring tool 100 may further include a connection portion 114 (e.g., an American Petroleum Institute standard pin connection) at a trailing end 118 of the earth-boring tool 100. An internal bore 116 may extend from the trailing end 118 toward a leading end 120 of the earth-boring tool 100. The internal bore 116 may be in fluid communication with fluid passageways 122 extending from the internal bore 116 to an exterior of the earth-boring tool 100, enabling fluid circulating through the earth-boring tool 100 to flow from the internal bore 116, through the fluid passageways 122, to nozzles exposed in the junk slots 110.

The passively adjustable elements 102 configured as depth-of-cut-control elements or ovoids may be secured to the blades 108 at locations rotationally trailing the rotationally leading surfaces 112. Extension and retraction of the passively adjustable element 102 may modify an exposure E of the passively adjustable element 102 above the body 104. The degree to which the cutting elements 106 are overexposed relative to, exposed to the same degree as, or are underexposed relative to the passively adjustable elements 102 may change as the passively adjustable element 102 extends and retracts in response to applied forces resulting from contact with the earth material, providing passive adjustment of the depth of cut for those cutting elements 106. In other embodiments, passively adjustable elements in accordance with this disclosure may be beneficially employed in the same or other configurations on other types of earth-boring tools, such as, for example, other types of earth-boring drill bits, reamers, mills, stabilizers, etc.

The passively adjustable elements 102 may be located partially within pockets 124 extending at least partially through the body 104 of the earth-boring tool 100. For example, the pocket 124 may extend entirely through a portion of the body 104, enabling the passively adjustable elements 102 to be partially received into the pockets 124 while granting user access to both ends of the passively adjustable elements 102, such as, for example, to enable the user to install the passively adjustable elements 102 on the earth-boring tool 100. As shown in FIG. 1, the pockets 124 may extend, for example, from exposed surfaces of the blades 108 at the leading end 120 of the earth-boring tool 100, through the blades 106, to exposed surfaces of the blades 106 at the exterior of the earth-boring tool 100 located axially between the leading end 120 and the trailing end 118. In other embodiments, the pockets may extend from the exterior of the earth-boring tool 100 or other earth-boring tools beginning at other locations where contact between a passively adjustable element 102 and an earth formation may be desired, such as, for example, proximate the rotationally leading surfaces 112 of the blades, proximate gage regions 126 at radially outermost portions of the blades 108, or proximate radially outer portions of stabilizer arms. The pockets may extend from the exterior of the earth-boring tool 100 or other earth-boring tools ending at other locations in other embodiments, such as, for example, within the internal bore 116 or in the junk slots 110.

FIG. 2 is a cross-sectional side view of the passively adjustable element 102 of FIG. 1 in a retracted state. The passively adjustable element 102 may include a housing 128 configured to be secured to the earth-boring tool 100 (see FIG. 1) and to support other components of the passively adjustable element 102 at least partially within the housing 128. The housing 128. The housing 128 may include, for example, a generally tube-shaped member having a first opening 130 at a first end 132 of the housing 128 and a second opening 134 at a second end 136 of the housing 128.

An element 138 may be located at least partially within the housing 128. The element 138 may be positioned at least partially within the first opening 130 at the first end 132 of the housing 128. The element 138 may be extendable and retractable relative to the housing 128. As shown in FIG. 2, the element 138 may extend beyond the first end 132 of the housing 128 when the element 138 is in the retracted state. In other embodiments, an extended-most portion 140 of the element 138 may be flush with the first end 132 or may be recessed within the first opening 130. When the element 138 is configured as a depth-of-cut-control element or ovoid, as shown in FIG. 2, the extended-most portion 140 of the element 138 may be curved, such as, for example, in a dome shape. A wiper element 142 may be located within a recess 144 in an inner surface 146 of the housing 128 and in contact with the element 138. The wiper element 142 may be configured to remove environmental fluids (e.g., circulating drilling fluid) from side surfaces 148 of the element 138 as the element 138 extends and retracts, reducing the likelihood that the environmental fluids will flow beyond the wiper element 142 into an interior 150 of the housing 128, potentially contaminating the interior 150.

A piston 152 may be located within the housing 128 and secured to the element 138. For example, the element 138 may be secured to a seat 154 (e.g., by brazing) located on a first end 156 of the piston 152 proximate to the first end 132 of the housing 128. The seat 154 may have an annular shape with a ledge 160 on which the element 138 may be supported and an outer ring 162 laterally surrounding a retracted-most end 158 of the element 138. The piston 152 may be configured to drive extension and retraction of the element 138. The piston 152 may generally have a cylindrical shape, and the piston 152 may be located entirely within the interior 150 of the housing 128. The piston 152 may include a longitudinal axis 174 extending along an average geometrical center of the piston 152 from proximate to the first end 132 of the housing 128 toward the second, opposite end 136 of the housing 128.

The piston 152 and the housing 128 cooperatively form a first chamber 164 located at a first axial position 166 along the piston 152 and a second chamber 168 located at a second, different axial position 170 along the piston 152. Volumes of the first chamber 164 and second chamber 168 may change as the piston 152 and element 138 extend and retract. As shown in FIG. 2, the volume of the first chamber 164 may be at its minimum value, and the volume of the second chamber 168 may be at its maximum value, when the element 138 is in the fully retracted position. The first chamber 164 may be located proximate a second, opposite end 172 of the piston 152 distal from the element 138, and the second chamber 168 may be located on an axial side of the first chamber 164 opposite the second end 136 of the housing 128.

In some embodiments, the passively adjustable element 102 may include only the first chamber 164 and the second chamber 168. In other embodiments, such as that shown in FIG. 2, the piston 152 and the housing 128 may further cooperatively form a third chamber 176 located at a third, different axial position 178 along the piston 152 and a fourth chamber 180 located at a fourth, different axial position 182 along the piston 152. The third chamber 176 may be in fluid communication with the first chamber 164, such that a pressure in the first chamber 164 and a pressure in the third chamber 176 may be at least substantially equal, and may be located on an axial side of the second chamber 168 opposite the first chamber 164. The fourth chamber 180 may be in fluid communication with the second chamber 168, such that a pressure in the second chamber 168 and a pressure in the fourth chamber 180 may be at least substantially equal, and may be located on an axial side of the third chamber 176 opposite the second chamber 168. As shown in FIG. 2, the volume of the third chamber 176 may be at its minimum value (e.g., the fifth portion 194 of the piston 152 may be located proximate to, or even be in contact with, the flange 190), and the volume of the fourth chamber 180 may be at its maximum value, when the element 138 is in the fully retracted position.

The first chamber 164 may be formed between the inner surface 146 of the housing 128 and a first portion 184 of the piston 152 having a first diameter D₁ at the second end 172 of the piston 152, leaving an at least substantially annular space between the first portion 184 of the piston 152 and the inner surface 146 of the housing 128. The piston 152 may include a second portion 186 located axially adjacent to the first portion 184 on a side of the first portion 184 proximate to the element 152, the second portion 186 having a second, larger diameter D₂. The second portion 186 may extend radially proximate to the inner surface 146 of the housing 128, and may optionally be in sliding contact with the inner surface 146 of the housing 128. The second chamber 168 may be formed between the inner surface 146 of the housing 128 and a third portion 188 of the piston 152 having the first diameter D₁ (or another reduced diameter relative to the second, larger diameter D₂) on an axial side of the second portion 186 opposite the first portion 184, leaving another at least substantially annular space between the third portion 188 of the piston 152 and the inner surface 146 of the housing 128. A flange 190 of the housing 128 may extend radially inward on an axial side of the second chamber 168 opposite the second portion 186 of the piston 152, such that the second chamber 168 may be formed axially between the second portion 186 of the piston 152 and the flange 190 of the housing 128, and radially between the third portion 188 of the piston 152 and the inner surface 146 of the housing 128.

The third chamber 176 may be formed between the inner surface 146 of the housing 128 and a fourth portion 192 of the piston 152 having the first diameter D₁ (or another reduced diameter relative to the second, larger diameter D₂) on an axial side of the flange 190 opposite the third portion 188, leaving another at least substantially annular space between the fourth portion 192 of the piston 152 and the inner surface 146 of the housing 128. The fourth chamber 180 may be formed radially between the inner surface 146 of the housing 128 and a fifth portion 194 of the piston 152 having the second diameter D₂ (or another diameter greater than the first diameter D₁) on an axial side of the fourth portion 192 opposite the flange 190, leaving another at least substantially annular space between the third portion 188 of the piston 152 and the inner surface 146 of the housing 128. The fourth chamber 180 may also extend axially along a sixth portion 196 of the piston 152 extending from the fifth portion 194 to the seat 154, and having a third diameter D₃ between the first diameter D₁ and the second diameter D₂.

Sealing elements may fluidly isolate the various chambers from one another. For example, a first sealing element 198 may be positioned partially within a first recess 200 in the second portion 186 of the piston 152, and may be in sealing contact with the inner surface 146 of the housing 128, to separate the first chamber 164 from the second chamber 168. A second sealing element 202 may be positioned partially within a second recess 204 in the flange 190 of the housing 128, and may be in sealing contact with the third portion 188 and the fourth portion 192 of the piston 152, to separate the second chamber 168 from the third chamber 176. A third sealing element 206 may be positioned partially within a third recess 208 in the fifth portion 194 of the piston 152 proximate to the flange 190, and may be in sealing contact with the fourth portion 192. A fourth sealing element 210 may be positioned partially within a fourth recess 212 in the fifth portion 194 of the piston 152 proximate to the sixth portion 196, and may be in sealing contact with the fourth portion 192. A fifth sealing element 214 may be positioned partially within a fifth recess 216 in the fifth portion 194 of the piston 152 axially between the third recess 208 and the fourth recess 212, and may be in sealing contact with the inner surface 146 of the housing 128. The third sealing element 206, fourth sealing element 210, and fifth sealing element 214 may cooperatively separate the third chamber 176 from the fourth chamber 180. Another wiper element 218 may be located within another recess 220 in the inner surface 146 of the housing 128 and in contact with the sixth portion 196 proximate to the seat 154. The other wiper element 218 may be configured to remove environmental fluids (e.g., circulating drilling fluid) from side surfaces 148 of the sixth portion 196 as the piston 152 extends and retracts, reducing the likelihood that the environmental fluids will flow beyond the other wiper element 218 into the interior 150 of the housing 128, potentially contaminating the interior 150.

Flow paths may place the various chambers into fluid communication with one another, and flow regulators may regulate the flow of fluid between the chambers to control rates at which the piston 152 and element 138 extend and retract. For example, a first flow path 222 may extend from the first chamber 164 and from the third chamber 176, through the first portion 184, second portion 186, third portion 188, and fourth portion 190 of the piston 152, to a first flow controller 224 supported by the piston 152 in a recess 226 in the fifth portion 194 proximate to the sixth portion 196. The first flow controller 224 may be configured to permit fluid to flow through the first flow controller 224 at a first rate. The first flow controller 224 may include, for example, a restrictor. When fluid exits the first flow controller 224, the fluid may flow into the fourth chamber 180. A second flow path 228, for example, may extend from the second chamber 168 and the fourth chamber 180, through the fifth portion 194, fourth portion 192, third portion 188, second portion 186, and first portion 184 of the piston 152, to a second flow controller 230 supported by the piston 152 in another recess 232 in the first portion 184 proximate to the second end 172 of the piston 152. The second flow controller 230 may be configured to permit fluid to flow through the second flow controller 230 at a second, faster rate. The second flow controller 230 may include, for example, a check valve. Because the fluid may flow through the second flow path 228 more quickly than the fluid flows through the first flow path 222, the piston 152 and element 138 may extend to an extended state more quickly than the piston 152 and the element 138 may retract to the retracted state.

A first angle Θ₁ between a geometric center of the first flow path 222 from the first chamber 164 into the piston 152 and the longitudinal axis 174 of the piston 152 may be oblique. For example, the first angle Θ₁ between the first flow path 222 and the longitudinal axis 174 may be between about 30° and about 60°. As a specific, nonlimiting example, the first angle Θ₁ between the first flow path 222 and the longitudinal axis 174 may be about 45°. A second angle Θ₂ between a geometric center of the second flow path 228 from the fourth chamber 180 into the piston 152 may be, for example, perpendicular to the longitudinal axis 174 of the piston 152. A third angle Θ₃ between a geometric center of the second flow path 228 from the second chamber 168 into the piston 152 and the longitudinal axis 174 of the piston 152 may be oblique. For example, the third angle Θ₃ between the second flow path 228 and the longitudinal axis 174 may be between about 30° and about 60°. As a specific, nonlimiting example, the third angle Θ₃ between the second flow path 228 and the longitudinal axis 174 may be about 45°. Rendering portions of the first flow path 222 and the second flow path 228 non-parallel to the longitudinal axis 174 may enable the size of the passively adjustable element 102 to be reduced.

A biasing element 234 may be positioned to bias the piston 152 and the element 138 toward the extended position. For example, the biasing element 234 may include a spring (e.g., a coiled spring, a wave spring, a resilient polymer material), which may be located within the first chamber 164 and may bear against the second portion 186 of the piston 152 and a cap 236 closing the second opening 134 at the second end 136 of the housing 128.

A greatest outer diameter of the piston 152, which may be the second diameter D₂, may be, for example, less than or at least substantially equal to the greatest outer diameter OD of the element 138. Use of the term outer diameter herein is not to be construed as a limitation on the cross-sectional shapes of the piston 152 and the element 138. For example, the piston 152 and the element 138 may have circular cross-sectional shapes in planes perpendicular to the longitudinal axis 174, or may have other cross-sectional shapes in those planes (e.g., rectangular, obround, oval), and the outer diameter may be measured as the largest linear dimension between outer points as measured in a plane perpendicular to the longitudinal axis 174. Keeping the piston 152 within the lateral extent of the element 138 may reduce the size of the passively adjustable element 102.

A pressure-compensating element 238 may be located within the housing 128. The pressure-compensating element 238 may be configured to move relative to the housing 128 to expand and contract a compensating volume 240 in response to extension and retraction of the piston 152 and the element 138 to compensate for temporary pressure differences between the first chamber 164 and the second chamber 168, and between the third chamber 176 and the fourth chamber 180. The pressure-compensating element 238 may be located, for example, on an axial side of the second chamber 168 opposite the first chamber 164 and proximate to the element 138. More specifically, the pressure-compensating element 238 may be located between the fourth chamber 180 and the seat 154, and the compensating volume 240 may be located in the fourth chamber 180. The pressure-compensating element 238 may include a pressure-compensating piston configured to move in a same direction as the piston 152 and the element 138, at least substantially parallel to the longitudinal axis 174, during extension and retraction. More specifically, the pressure-compensating element 238 may be configured as an annular piston located radially around the sixth portion 196 of the piston 152, and longitudinally between the fourth chamber 180 and any environmental fluid located on a side of the pressure-compensating element 238 opposite the fourth chamber 180. The pressure-compensating element 238 may include sealing elements 242, one in sealing contact with the inner surface 146 of the housing 128 and another in sealing contact with the sixth portion 196 of the piston 152. Because the greatest diameter D₂ of the piston 152 may be reduced, the pressures experienced in the interior 150 of the housing 102 may be increased, and the pressure-compensating element 238 may reduce the likelihood that the pressures in the interior 150 exceed maximum thresholds.

The materials of the various components of the passively adjustable element 102 may be selected to withstand the pressures, forces, vibrations, temperatures, and potentially corrosive materials encountered in the downhole environment. For example, appropriate materials may include metals, metal alloys (e.g., steel), ceramics, ceramic-metallic composite materials (e.g., cobalt-bound particles of tungsten carbide), and polymers (e.g., rubber).

The element 138 and piston 152 may move to the retracted position in response to applied forces on the element 138. In response to the applied forces, the element 138 and piston 152 may move in a direction from the first end 132 of the housing 128 toward the second end 136 of the housing 128. That movement may compress the biasing element 234, overcoming its bias force toward the extended position. That movement may also compress the volumes of the first chamber 164 and the third chamber 176, causing fluid to flow from the first chamber 164 and the third chamber 176, through the first flow path 222, to the first flow controller 224. The first flow controller 224 may ensure that a rate at which the fluid flows from the first flow path 222 into the fourth chamber 180 and the second chamber 168 as the volumes of the fourth chamber 180 and the second chamber 168 expand due to movement of the piston 152 occurs at a controlled, relatively slow rate. To compensate for pressure spikes and temporary pressure differences, the pressure-compensating element 238 may move to expand, retract, or maintain at least substantially constant, the total volumes of the fourth chamber 180 and second chamber 168.

FIG. 3 is a cross-sectional side view of the passively adjustable element 102 of FIG. 2 in an extended state. The element 138 and piston 152 may move to the extended position in response to reduction in applied forces on the element 138 below a biasing force of the biasing element 234. In response to the biasing force, the element 138 and piston 152 may move in a direction from the second end of the housing 128 toward the first end 132 of the housing 128. That movement may expand the biasing element 234. That movement may also compress the volumes of the second chamber 168 and the fourth chamber 180, causing fluid to flow from the second chamber 168 and the fourth chamber 180, through the second flow path 228, to the second flow controller 230. The second flow controller 230 may ensure that a rate at which the fluid flows from the second flow path 228 into the first chamber 164 and the third chamber 176 as the volumes of the first chamber 164 and the third chamber 176 expand due to movement of the piston 152 occurs at a controlled, relatively quicker rate. To compensate for pressure spikes and temporary pressure differences, the pressure-compensating element 238 may move to expand, retract, or maintain at least substantially constant, the total volumes of the fourth chamber 180 and second chamber 168. When the element 138 is in the extended position, the extended-most portion 140 of the element 138 may extend beyond the housing 128 to a desired maximum exposure.

To assemble the passively adjustable element 102, the fourth portion 192 of the piston 152 may be inserted from the opening 134 at the second end 136 of the housing 128, through the flange 190 of the housing 128, into the third chamber 176, which may place the first portion 184 carrying the second flow controller 230 in the first chamber 164, the second portion 186 in contact with the inner surface 146 of the housing 128, and the third portion 188 in the second chamber 168. The first portion 184, second portion 186, third portion 188, and fourth portion 192 of the piston 152 may be provided as a distinct component of the piston 152. The biasing element 234 may be placed in contact with the second portion 186 of the piston 152 within the first chamber 164. The cap 236 may be secured to the housing 128, such as, for example, by engaging a threaded pin of the cap 236 with a threaded box of the housing 128 at the second end 136. The fifth portion 194, with the first flow controller 224 supported therein, may be introduced from an intermediate opening 242 of the housing 128 located between the flange 190 and the first end 132, into contact with the fourth portion 192 and into the fourth chamber 180. The fifth portion 194 may be provided as another distinct component of the piston 152. The sixth portion 196, with the pressure-compensating element 238 supported thereon, may be introduced through the intermediate opening 242 into contact with the fifth portion 194. The first chamber 164, second chamber 168, third chamber 176, and fourth chamber 180 may be filled with a pressure-transmission fluid, such as, for example, a hydraulic fluid. The pressure-transmission fluid may be introduced via a fluid path 244 extending from an extended-most end 246 of the sixth portion 196, through the sixth portion 196, to the fourth chamber 180, and on to the first chamber 164, second chamber 168, and third chamber 176 via the first flow path 222 and second flow path 228. A plug 248 may be secured to the sixth portion 196 in the fluid path 244 to seal the pressure-transmission fluid within the interior 150 of the housing 128. The first end 132 of the housing 128 may be secured to a remainder of the housing 128 with the element 138, seat 154, and wiper elements 142 and 218 therein. The first end 132 may include a ledge 250 against which the seat 154 may abut when the element 138 is in the extended position, delimiting extension of the element 138 and beneficially employing the biasing force of the biasing element 234 to maintain the assembly of the components within the interior 150 of the housing 128.

Once assembled, the passively adjustable element 102 may be installed in an earth-boring tool 100 (see FIG. 1) by placing the passively adjustable element 102 at least partially within the pocket 124 and utilizing an attachment mechanism 250 to secure the passively adjustable element 102 within the pocket 124. As shown in FIG. 3, the attachment mechanism 250 may be configured as a split ring, including a split ring 252 configured to expand radially and an expander 254 shaped to force the split ring 252 to expand radially when the expander is secured to the cap 236 (e.g., by engaging a threaded pin of the expander 254 with a threaded box on a side of the cap 236 opposite the housing 128). The split ring 252 may be aligned with a groove 256 extending radially outward in the pocket 124, and the expander 254 may be secured to the cap 236, causing the split ring 252 to expand radially into the complementary groove 256. The expander 254 may subsequently be detached, enabling the split ring 252 to retract, and the passively adjustable element 102 to be removed from the pocket 124. If still operable, the passively adjustable element 102 may then be installed on another earth-boring tool. If inoperable, the passively adjustable element 102 may be replaced with another passively adjustable element or repaired and installed on the same earth-boring tool 100 (see FIG. 1) or on another earth-boring tool.

FIG. 4 is a cross-sectional side view of another embodiment of a passively adjustable element 260. The passively adjustable element 260 may be configured at least substantially similarly to the passively adjustable element 102 of FIGS. 1 through 3, with at least three notable exceptions. First, the fluid path 262 for introducing the pressure-transmission fluid into the interior 150 of the housing 128 may be located proximate to the second end 136 of the housing 128, rather than proximate to the intermediate opening 242. As a result, the sixth portion 196 of the piston 152 may be a solid part, lacking any fluid passageways therethrough. The fluid path 262 may extend through the cap 264 at the second end 136 of the housing 128, such that pressure-transmission fluid introduced through the fluid path 262 may first enter the first chamber 164 and flow therefrom, through the first flow path 222 and the second flow path 228, to the second chamber 168, third chamber 176, and fourth chamber 180. The plug 248 may be received into the fluid path 262 in the cap 264 to enclose the interior 150 of the housing 128 when sufficient pressure-transmission fluid has been introduced.

Second, the pressure-compensating element 266 may be configured as a diaphragm configured to expand and retract laterally relative to the piston 152 during extension and retraction of the element 272. The pressure-compensating element 266 configured as a diaphragm may extend axially from a recess 268 in the housing 128 radially adjacent to the sixth portion 196 and axially proximate to the fifth portion 194 to a clamp ring 270 securing the pressure-compensating element 266 around the sixth portion 196 of the piston 152 proximate to the wiper elements 218. The pressure-compensating element 266 may expand radially outward toward the housing 128, and contract radially inward toward the sixth portion 196, to compensate for pressure spikes and temporary pressure differences within the interior 150 of the housing 128.

Finally, the element 272 may be configured as a stabilizer pad or a gage pad, rather than a depth-of-cut-control element or ovoid. The extended-most portion 274 of the element 272 may be curved to at least substantially follow a rotational path of the passively adjustable element 260, such that the extended-most portion 274 may be configured for nonaggressive, sliding contact with earth material.

FIG. 5 is a cross-sectional side view of yet another embodiment of a passively adjustable element 280. The passively adjustable element 280 may be configured at least substantially similarly to the passively adjustable element 102 of FIGS. 1 through 3, with several notable exceptions discussed below. The passively adjustable element 280 may lack the third chamber 176 and the fourth chamber 180 (see FIGS. 1 through 4). To facilitate such an arrangement, the housing 288 may lack the flange 190 (see FIGS. 1 through 4) and the fifth portion 194 may directly abut the third portion 188 and fourth portion 192 (e.g., by receiving them into a recess in the fifth portion 194). The first flow path 282 may extend axially from the first chamber 164, through a radially central portion of the piston 152, to the first flow controller 224. The second flow path 284 may extend from the second chamber 286, initially in a direction perpendicular to the longitudinal axis 174, into a space laterally between the piston 152 and the inner surface 146 of the housing 288 and returning axially toward the first chamber 164, and finally in the direction perpendicular to the longitudinal axis 174 to the second flow controller 230. The second end 136 of the housing 228 may lack the opening 134 (see FIGS. 1 through 4), and may simply be enclosed. The compensating element 238 may be configured as a piston radially surrounding the fifth portion 194, and the compensating volume 290 may be located in the second chamber 286.

In addition, the element 292 may be configured as a cutting element or a cutting insert, rather than a depth-of-cut-control element, an ovoid, a stabilizer pad, or a gage pad. The extended-most portion 294 of the element 292 may include a cutting face configured for aggressive, earth-removing contact with earth material.

FIG. 6 is a cross-sectional side view of still another embodiment of a passively adjustable element 300. The passively adjustable element 300 may be configured at least substantially similarly to the passively adjustable element 102 of FIGS. 1 through 3, with several notable exceptions discussed below. First, the pressure-compensating element 302 may be configured as a piston located proximate to the second end 136 of the housing 304, such that the pressure-compensating element 302 may be located on an axial side of the first chamber 164 opposite the second chamber 168 and opposite the element 138. To facilitate such an arrangement, the compensating volume 316 may be formed between the pressure-compensating element 302 and the cap 318, which may support the second flow controller 230 on a side of the compensating volume 316 opposite the pressure-compensating element 302. The pressure-compensating element 302 may move parallel to the longitudinal axis 174 to expand and contract the compensating volume 316 to compensate for temporary pressure differences and pressure spikes. The compensating volume 316 may be in fluid communication with the fourth chamber 180 via, and may form a part of, the second flow path 320.

Second, at least a portion of the second flow path 320 may be formed by a passageway extending through the tubular sidewall of the housing 304. For example, the first flow path 322 may extend from the first chamber 164 and the third chamber 176, through the piston 324 (e.g., parallel to the longitudinal axis 174 from the first chamber 164 and initially perpendicular to the longitudinal axis 174 from the third chamber 176), to the first flow controller 224.The second flow path 320 may extend from the second chamber 168 and the fourth chamber 180, radially outward through the inner surface 146 of the housing 304 (e.g., directly through the inner surface 146 of the housing 304 or initially through the sixth portion 196 of the piston 324 and then through the inner surface 146 of the housing 304), axially within the housing 304 toward, and then radially into, the compensating volume 316, and to the second flow controller 230.

FIG. 7 is a cross-sectional side view of yet another embodiment of a passively adjustable element 330. The passively adjustable element 330 may be configured at least substantially similarly to the passively adjustable element 300 of FIG. 6 with two notable exceptions. First, the pressure-compensating element 332 may be configured as a diaphragm extending laterally across the cap, the diaphragm of the pressure-compensating element 332 configured to expand and contract to compensate for temporary pressure differences and pressure spikes.

Second, the attachment mechanism 334 may be configured as a collet. For example, a sleeve 336 of the attachment mechanism 334 may include a first set of threads 336 located at a radial exterior of the sleeve 344, which first set of threads 344 may threadedly engage with complementary threads 338 in the pocket 124. The sleeve 336 may include a second set of threads 340 located at a radial interior of the sleeve 336, which second set of threads 340 may threadedly engaged with complementary threads 342 on the cap 346 or on the housing 304 to secure the passively adjustable element 340 within the pocket 124 via the sleeve 336.

Passively adjustable elements in accordance with this disclosure may be smaller in size, particularly in the lateral/radial direction; easier to assemble, install, remove, replace, repair, and maintain; and may better accommodate increased pressures that accompany reduction in size.

Though several different embodiments have been shown and described in connection with the various figures, those skilled in the art will recognize that a feature or features of one embodiments may be interchanged with a feature or features of one or more of the other embodiments while still falling within the scope of this disclosure. For example, the different configurations for the element may be employed with any of the configurations for the piston, chambers, flow paths, attachment mechanism, and/or pressure-compensating element. When the different features and configurations disclosed for the elements, pistons, chambers, flow paths, attachment mechanisms, and/or pressure-compensating elements are physically combinable, those combinations are expressly contemplated under this disclosure.

Additional, nonlimiting embodiments within the scope of this disclosure include the following:

Embodiment 1: A passively adjustable element for an earth-boring tool, comprising: a housing; an element located at least partially within the housing and extendable and retractable relative to the housing; a piston located within the housing and secured to the element, the piston configured to drive extension and retraction of the element, wherein the piston and the housing cooperatively form a first chamber located at a first axial position along the piston and a second chamber located at a second, different axial position along the piston; a first flow path extending from the first chamber, through the piston, through a first flow controller supported by the piston, to the second chamber, the first flow controller configured to permit fluid to flow from the first chamber to the second chamber at a first rate during retraction of the element and piston relative to the housing; a second flow path extending from the second chamber, at least partially through the piston, through a second flow controller supported by the piston, to the first chamber, the second flow controller configured to permit fluid to flow from the second chamber to the first chamber at a second, faster rate during extension of the element and piston relative to the housing; at least one sealing element located between the piston and the housing to axially separate the first chamber from the second chamber; and a biasing element positioned and configured to bias the piston and element toward an extended position; wherein an outer diameter of the piston as measured in a direction at least substantially perpendicular to a direction of extension and retraction of the element is at least substantially equal to an outer diameter of the element.

Embodiment 2: The passively adjustable element of Embodiment 1, wherein the piston and the housing further cooperatively form a third chamber located at a third, different axial position along the piston and a fourth chamber located at a fourth, different axial position along the piston, the third chamber in fluid communication with the first chamber via the first flow path and located on an axial side of the second chamber opposite the first chamber, the fourth chamber in fluid communication with the second chamber via the second flow path and located on an axial side of the third chamber opposite the second chamber.

Embodiment 3: The passively adjustable element of Embodiment 2, wherein the compensating volume is in the fourth chamber.

Embodiment 4: The passively adjustable element of any one of Embodiments 1 through 3, wherein an angle between a geometric center of the first flow path from the first chamber into the piston and a longitudinal axis of the piston is oblique.

Embodiment 5: The passively adjustable element for an earth-boring tool of Embodiment 4, wherein the angle is about 45°.

Embodiment 6: The passively adjustable element of any one of Embodiments 1 through 5, wherein a geometric center of the second flow path from the second chamber into the piston is perpendicular to a longitudinal axis of the piston.

Embodiment 7: The passively adjustable element of any one of Embodiments 4 through 6, wherein the first chamber is located on an axial side of the second chamber opposite the element extendable and retractable relative to the housing.

Embodiment 8: The passively adjustable element of Embodiment 7, wherein the biasing element is located in the first chamber.

Embodiment 9: The passively adjustable element of any one of Embodiments 1 through 4, further comprising a pressure-compensating element located within the housing, the pressure-compensating element configured to move relative to the housing to expand and contract a compensating volume in response to extension and retraction of the piston and the element to compensate for temporary pressure differences between the first chamber and the second chamber.

Embodiment 10: The passively adjustable element of Embodiment 9, wherein the compensating volume is in the second chamber.

Embodiment 11: The passively adjustable element of any one of Embodiment 9, wherein the pressure-compensating element is located on an axial side of the second chamber opposite the first chamber and proximate to the element.

Embodiment 12: The passively adjustable element of Embodiment 9, wherein the pressure-compensating element is located on an axial side of the first chamber opposite the second chamber and opposite the element.

Embodiment 13: The passively adjustable element of any one of Embodiments 1 through 12, wherein the pressure-compensating element comprises a pressure-compensating piston configured to move in a same direction as the piston and the element during extension and retraction.

Embodiment 14: The passively adjustable element of any one of Embodiments 1 through 13, wherein the pressure-compensating element comprises a diaphragm configured to expand and retract laterally relative to the piston during extension and retraction of the element.

Embodiment 15. The passively adjustable element of any one of Embodiments 1 through 14, wherein the element is selected from the group consisting of: a cutting element, a cutting insert, a depth-of-cut-control element, an ovoid, a gage pad, and a stabilizer pad.

Embodiment 16: The passively adjustable element of any one of Embodiments 1 through 15, wherein the first flow controller comprises a restrictor and the second flow controller comprises a check valve.

Embodiment 17: An earth-boring tool, comprising: a body; and a passively adjustable element secured to the body, the passively adjustable element comprising: a housing secured within a pocket extending into the body; an element located at least partially within the housing and extendable and retractable relative to the housing; a piston located within the housing and secured to the element, the piston configured to drive extension and retraction of the element, wherein the piston and the housing cooperatively form a first chamber located at a first axial position along the piston and a second chamber located at a second, different axial position along the piston; a first flow path extending from the first chamber, through the piston, through a first flow controller supported by the piston, to the second chamber, the first flow controller configured to permit fluid to flow from the first chamber to the second chamber at a first rate during retraction of the element and piston relative to the housing; a second flow path extending from the second chamber, at least partially through the piston, through a second flow controller supported by the piston, to the first chamber, the second flow controller configured to permit fluid to flow from the second chamber to the first chamber at a second, faster rate during extension of the element and piston relative to the housing; at least one sealing element located between the piston and the housing to axially separate the first chamber from the second chamber; and a biasing element positioned and configured to bias the piston and element toward an extended position; wherein an outer diameter of the piston as measured in a direction at least substantially perpendicular to a direction of extension and retraction of the element is less than or at least substantially equal to an outer diameter of the element.

Embodiment 18: The earth-boring tool of Embodiment 17, wherein the housing of the passively adjustable element is secured within the pocket by a split ring forced at least partially into a complementary groove in the pocket by an expander.

Embodiment 19: The earth-boring tool of Embodiment 17, wherein the housing of the passively adjustable element is secured within the pocket by a collet secured within the pocket and threadedly engaged with the housing.

Embodiment 20: A method of using an earth-boring tool having a passively adjustable element, comprising: engaging an earth formation utilizing an earth-boring tool; retracting at a first rate an element to a greater extent within a housing secured to a body of the earth-boring tool in response to engaging the earth formation utilizing the earth-boring tool by compressing a biasing element biasing the piston and the element toward an extended position while flowing a hydraulic fluid along a first flow path extending from a first chamber located at a first axial position along a piston secured to, and movable with, the element, through the piston, through a first flow controller supported by the piston, to a second chamber located at a second, different axial position along the piston, an outer diameter of the piston as measured in a direction at least substantially perpendicular to a direction of extension and retraction of the element being less than or at least substantially equal to an outer diameter of the element; extending at a second, faster rate the element relative to the housing in response to reducing engagement with the earth formation utilizing the earth-boring tool by permitting the biasing element to move the piston and the element toward the extended position while flowing the hydraulic fluid along a second flow path extending from the second chamber, at least partially through the piston, through a second flow controller supported by the piston, to the first chamber; and fluidly isolating the first chamber from the second chamber utilizing at least one sealing element located between the piston and the housing.

Embodiment 21: The passively adjustable element of Embodiment 20, wherein flowing the hydraulic fluid along the first flow path extending from the first chamber comprises flowing the hydraulic fluid along the first flow path at an oblique angle as measured between a geometric center of the first flow path from the first chamber into the piston and a longitudinal axis of the piston.

While certain illustrative embodiments have been described in connection with the figures, those of ordinary skill in the art will recognize and appreciate that the scope of this disclosure is not limited to those embodiments explicitly shown and described in this disclosure. Rather, many additions, deletions, and modifications to the embodiments described in this disclosure may be made to produce embodiments within the scope of this disclosure, such as those specifically claimed, including legal equivalents. In addition, features from one disclosed embodiment may be combined with features of another disclosed embodiment while still being within the scope of this disclosure, as contemplated by the inventors. 

1. A passively adjustable element for an earth-boring tool, comprising: a housing; an element located at least partially within the housing and extendable and retractable relative to the housing; a piston located within the housing and secured to the element, the piston configured to drive extension and retraction of the element, wherein the piston and the housing cooperatively form a first chamber located at a first axial position along the piston and a second chamber located at a second, different axial position along the piston; a first flow path extending from the first chamber, through the piston, through a first flow controller supported by the piston, to the second chamber, the first flow controller configured to permit fluid to flow from the first chamber to the second chamber at a first rate during retraction of the element and piston relative to the housing; a second flow path extending from the second chamber, at least partially through the piston, through a second flow controller supported by the piston, to the first chamber, the second flow controller configured to permit fluid to flow from the second chamber to the first chamber at a second, faster rate during extension of the element and piston relative to the housing; at least one sealing element located between the piston and the housing to axially separate the first chamber from the second chamber; and a biasing element positioned and configured to bias the piston and element toward an extended position; wherein an outer diameter of the piston as measured in a direction at least substantially perpendicular to a direction of extension and retraction of the element is less than or at least substantially equal to an outer diameter of the element.
 2. The passively adjustable element of claim 1, wherein the piston and the housing further cooperatively form a third chamber located at a third, different axial position along the piston and a fourth chamber located at a fourth, different axial position along the piston, the third chamber in fluid communication with the first chamber via the first flow path and located on an axial side of the second chamber opposite the first chamber, the fourth chamber in fluid communication with the second chamber via the second flow path and located on an axial side of the third chamber opposite the second chamber.
 3. The passively adjustable element of claim 2, further comprising a pressure-compensating element located within the housing, the pressure-compensating element configured to move relative to the housing to expand and contract a compensating volume located in the fourth chamber in response to extension and retraction of the piston and the element to compensate for temporary pressure differences between the first chamber and the second chamber.
 4. The passively adjustable element of claim 1, wherein an angle between a geometric center of the first flow path from the first chamber into the piston and a longitudinal axis of the piston is oblique.
 5. The passively adjustable element of claim 4, wherein the angle is about 45°.
 6. The passively adjustable element of claim 1, wherein a geometric center of the second flow path from the second chamber into the piston is perpendicular to a longitudinal axis of the piston.
 7. The passively adjustable element of claim 1, wherein the first chamber is located on an axial side of the second chamber opposite the element extendable and retractable relative to the housing.
 8. The passively adjustable element of claim 7, wherein the biasing element is located in the first chamber.
 9. The passively adjustable element of claim 1, further comprising a pressure-compensating element located within the housing, the pressure-compensating element configured to move relative to the housing to expand and contract a compensating volume in response to extension and retraction of the piston and the element to compensate for temporary pressure differences between the first chamber and the second chamber.
 10. The passively adjustable element of claim 9, wherein the compensating volume is in the second chamber.
 11. The passively adjustable element of claim 9, wherein the pressure-compensating element is located on an axial side of the second chamber opposite the first chamber and proximate to the element.
 12. The passively adjustable element of claim 9, wherein the pressure-compensating element is located on an axial side of the first chamber opposite the second chamber and opposite the element.
 13. The passively adjustable element of claim 9, wherein the pressure-compensating element comprises a pressure-compensating piston configured to move in a same direction as the piston and the element during extension and retraction.
 14. The passively adjustable element of claim 9, wherein the pressure-compensating element comprises a diaphragm configured to expand and retract laterally relative to the piston during extension and retraction of the element.
 15. The passively adjustable element of claim 1, wherein the element is selected from the group consisting of: a cutting element, a cutting insert, a depth-of-cut-control element, an ovoid, a gage pad, and a stabilizer pad.
 16. The passively adjustable element of claim 1, wherein the first flow controller comprises a restrictor and the second flow controller comprises a check valve.
 17. An earth-boring tool, comprising: a body; and a passively adjustable element secured to the body, the passively adjustable element comprising: a housing secured within a pocket extending into the body; an element located at least partially within the housing and extendable and retractable relative to the housing; a piston located within the housing and secured to the element, the piston configured to drive extension and retraction of the element, wherein the piston and the housing cooperatively form a first chamber located at a first axial position along the piston and a second chamber located at a second, different axial position along the piston; a first flow path extending from the first chamber, through the piston, through a first flow controller supported by the piston, to the second chamber, the first flow controller configured to permit fluid to flow from the first chamber to the second chamber at a first rate during retraction of the element and piston relative to the housing; a second flow path extending from the second chamber, at least partially through the piston, through a second flow controller supported by the piston, to the first chamber, the second flow controller configured to permit fluid to flow from the second chamber to the first chamber at a second, faster rate during extension of the element and piston relative to the housing; at least one sealing element located between the piston and the housing to axially separate the first chamber from the second chamber; and a biasing element positioned and configured to bias the piston and element toward an extended position; and wherein an outer diameter of the piston as measured in a direction at least substantially perpendicular to a direction of extension and retraction of the element is less than or at least substantially equal to an outer diameter of the element.
 18. The earth-boring tool of claim 17, wherein the housing of the passively adjustable element is secured within the pocket by a split ring forced at least partially into a complementary groove in the pocket by an expander.
 19. The earth-boring tool of claim 17, wherein the housing of the passively adjustable element is secured within the pocket by a collet secured within the pocket and threadedly engaged with the housing.
 20. A method of using an earth-boring tool having a passively adjustable element, comprising: engaging an earth formation utilizing an earth-boring tool; retracting at a first rate an element to a greater extent within a housing secured to a body of the earth-boring tool in response to engaging the earth formation utilizing the earth-boring tool by compressing a biasing element biasing the piston and the element toward an extended position while flowing a hydraulic fluid along a first flow path extending from a first chamber located at a first axial position along a piston secured to, and movable with, the element, through the piston, through a first flow controller supported by the piston, to a second chamber located at a second, different axial position along the piston, an outer diameter of the piston as measured in a direction at least substantially perpendicular to a direction of extension and retraction of the element being less than or at least substantially equal to an outer diameter of the element; extending at a second, faster rate the element relative to the housing in response to reducing engagement with the earth formation utilizing the earth-boring tool by permitting the biasing element to move the piston and the element toward the extended position while flowing the hydraulic fluid along a second flow path extending from the second chamber, at least partially through the piston, through a second flow controller supported by the piston, to the first chamber; and fluidly isolating the first chamber from the second chamber utilizing at least one sealing element located between the piston and the housing. 